The Fullscreen API adds methods to present a specific Element (and its descendants) in full-screen mode, and to exit full-screen mode once it is no longer needed. This makes it possible to present desired content—such as an online game—using the user's entire screen, removing all browser user interface elements and other applications from the screen until full-screen mode is shut off.

Note: Support for this API varies somewhat across browsers, with many requiring vendor prefixes and/or not implementing the latest specification. See the Browser compatibility section below for details on support for this API. You may wish to consider using a library such as Fscreen for vendor agnostic access to the Fullscreen API.

Interfaces

The Fullscreen API has no interfaces of its own. Instead, it augments several other interfaces to add the methods, properties, and event handlers needed to provide full-screen functionality. These are listed in the following sections.

Methods

The Fullscreen API adds methods to the Document and Element interfaces to allow turning off and on full-screen mode.

Methods on the Element interface

Asks the user agent to place the specified element (and, by extension, its descendants) into full-screen mode, removing all of the browser's UI elements as well as all other applications from the screen. Returns a Promise which is resolved once full-screen mode has been activated.

Properties

The Document interface provides properties that can be used to determine if full-screen mode is supported and available, and if full-screen mode is currently active, which element is using the screen.

The fullscreenEnabled property tells you whether or not it is possible to engage full-screen mode. This is false if full-screen mode is not available for any reason (such as the "fullscreen" feature not being allowed, or full-screen mode not being supported).

Event handlers

The Fullscreen API defines two events which can be used to detect when full-screen mode is turned on and off, as well as when errors occur during the process of changing between full-screen and windowed modes. Event handlers for these events are available on the Document and Element interfaces.

Note: These event handler properties are not available as HTML content attributes. In other words, you cannot specify event handlers for fullscreenchange and fullscreenerror in the HTML content. They must be added by JavaScript code.

Event handlers on documents

An event handler for the fullscreenchange event that's sent to a Document when that document is placed into full-screen mode, or when that document exits full-screen mode. This handler is called only when the entire document is presented in full-screen mode.

Events

The Fullscreen API defines two events which can be used to detect when full-screen mode is turned on and off, as well as when errors occur during the process of changing between full-screen and windowed modes.

Dictionaries

Controlling access

The availability of full-screen mode can be controlled using Feature Policy. The full-screen mode feature is identified by the string "fullscreen", with a default allow-list value of "self", meaning that full-screen mode is permitted in top-level document contexts, as well as to nested browsing contexts loaded from the same origin as the top-most document.

Usage notes

Users can choose to exit full-screen mode simply by pressing the ESC (or F11) key, rather than waiting for the site or app to programmatically do so. Make sure you provide, somewhere in your user interface, appropriate user interface elements that inform the user that this option is available to them.

Note: Navigating to another page, changing tabs, or switching to another application using any application switcher (or Alt-Tab) will likewise exit full-screen mode.

Example

In this example, a video is presented in a web page. Pressing the Return or Enter key lets the user toggle between windowed and full-screen presentation of the video.

This starts by looking at the value of the document's fullscreenElement attribute. In a real-world deployment, at this time, you'll want to check for prefixed versions of this (mozFullScreenElement, msFullscreenElement, or webkitFullscreenElement, for example). If the value is null, the document is currently in windowed mode, so we need to switch to full-screen mode; otherwise, it's the element that's currently in full-screen mode. Switching to full-screen mode is done by calling Element.requestFullscreen() on the <video> element.

If full-screen mode is already active (fullscreenElement is not null), we call exitFullscreen() on the document to shut off full-screen mode.